3. Install water-efficient showerheads. Showers account for 20 percent of total household water usage. Choose a showerhead that allows less than 2.5 gallons per minute and save 20,000 gallons of water each year.

4. Place a plastic bottle filled with water in your toilet tank to save 11 gallons of water per day.

6. Buy the most efficient hot water tank possible when it's time to replace your current model.

For under $25, you can install two low-flow showerheads, place bottles in the toilet tanks, install low-flow aerators on faucets, and repair dripping or leaky faucets and toilets. These few changes alone can save up to 30,000 gallons of water annually and should pay for themselves in under a year.